Add 1 tablespoon oil to the Instant Pot. Add cumin, turmeric, onions, garlic, and green chilies, mix well and cook for 2 minutes. Add 1/4 cup of water and deglaze the pot with a spatula clearing any browned bits from the pot. Add half of the tomatoes and mix well. Add the eggplant slices and salt. Close Instant Pot with pressure valve to sealing. Pressure cook for 4-6 minutes depending on the thickness of the slices and how much they are already cooked.
Allow Natural pressure release or quick release after 5 mins. Open the Instant Pot and set it to sauté mode. Mash the eggplant slices with a spatula or potato masher. Add half of the remaining tomatoes, scallions and cilantro. Allow any excess water to evaporate. Garnish with remaining tomatoes, scallions and cilantro. Enjoy with toasted naan, pita bread or chips.